SCO Unix, Xenix and ODT General FAQ

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How can I prevent a certain SCO Unix tty from being used?

(From a newsgroup post by Bela Lubkin):

 From: Bela Lubkin <belal@sco.com>
 Subject: Re: busying out a pseudo tty
 Date: 2 Oct 2003 17:31:04 -0400
 References: <c5a0626d.0310021152.1e7ec391@posting.google.com>
 
 PW Herman wrote:
 
 > Hi, I've got a weird problem with an old un-supported dentist program
 > that runs on Openserver 5.0.4.  For some reason, it gives error
 > messages in certain menus if the user logs in on ttyp2, ttyp3, ttyp4
 > or ttyp5.  Is there any way to make these 4 pseudo ttys appear to be
 > busy so nobody ever connects on them???
 
 If you open the master sides (/dev/ptyp2 etc.), they will be busied out.
 You can do that with a very simple shell script that you could e.g. run
 as an rc script.  For example,
 
   #!/bin/sh
 
   # Busy out ports ttyp2, 3, 4, 5 because "un-supported dentist program"
   # is allergic to them...
 
   sleep 1000000000 < /dev/ptyp2 &
   sleep 1000000000 < /dev/ptyp3 &
   sleep 1000000000 < /dev/ptyp4 &
   sleep 1000000000 < /dev/ptyp5 &
 
 Save as /etc/rc2.d/S99pty-hold or something like that.
 
 You can save a few processes if you wish (but this gets messy if you
 want to busy out dozens of ports):
 
   cd /dev
   sleep 1000000000 2<ptyp2 3<ptyp3 4<ptyp4 5<ptyp5 &
   # Note that shell syntax allows redirecting fd's 0-9, no higher: 10<
   # does not work.
 
 >Bela<
 
 

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